Hypocalcemia - it polietiologic pathological condition observed as a symptom of other clinical entities, which is based on a sharp or moderate decrease in the concentration of serum ionized calcium .Symptoms of hypocalcemia occur when violated various electrophysiological processes at the cellular level.
Of course, the definition of saturation index of ionized calcium in serum is not a routine screening algorithm examination of the patient, but the discovery of hidden hypocalcemia to diagnose a variety of medical conditions in need of early treatment (oncopathology, kidney failure and so on.).
Causes of hypocalcemia
most common etiopathogenetic factor provokes hypocalcemic syndrome is a complete absence or lack paratirokrinina that occurs in pathologies such as the hypoparathyroidism or paratirokrininovaya failure.
Another mechanism in the pathogenesis of hypocalcemia is paratirokrininovaya resistance of the peripheral-type, which is ineffective paratirokrinina effects on
paratirokrininovoy relative lack of activity occurs in conjunction with a rapid loss of calcium decompensation simultaneous functionality of the parathyroid glands, which are the major regulator of calcium metabolism.Thus, development of a fundamental element hypocalcemic syndrome is a disturbance parathyroid regulation directly or indirectly.
insufficient production of parathyroid hormone, sooner or later provoke the development of hyperphosphatemia and hypocalcemia.Auxiliary machinery provocation hypocalcemic syndrome is the lack of production of calcitriol (the active vitamin D) by the kidneys.The result of the above pathological disorders advocates of acid-base imbalance, accompanied by an increase in serum potassium, increased seizure due to increased tone of the muscle fibers.Thus, the basis of seizures, which is the classic one for flow hypocalcemia put sharp increase in the content of potassium in the muscle cells.
acute hypocalcemic syndrome is observed in various emergencies involving massive cytolytic process in the organs (severe polytrauma, crush syndrome, burn damage, shock, cytostatic therapy).In this situation, there is a rapid release of intracellular potassium phosphates with simultaneous reduction of the ionized calcium level in blood serum.In the case of joining signs of renal failure observed critical giperfosfatemicheskaya hypocalcemia.
also for acute hypocalcemia observed when using drugs that bind calcium in the blood and drugs that have a negative impact on calcium absorption in the small intestine and kidneys.Severe pancreatitis in the stage of pancreatic necrosis and is often accompanied by hypocalcemia due to increased formation of soap-like compounds containing calcium.
separate nosological form of hypocalcemia in infants, the origin of which is caused by insufficient intake of ionized calcium from mother's milk, and increased demand in this growing body nutrients.
rare cause of acute form of hypocalcemia is a kidney transplant as podsazhenny material long enough metabolize citric acid and provokes gipertsitrataemiyu.
most rare and at the same time dangerous to human life is a form of postpartum hypocalcemia, which in 90% of cases are fatal because of the lightning current tetanic convulsions.
Chronic hypocalcemia occurs with hypoparathyroidism, chronic renal failure and rickets.
Symptoms of hypocalcemia
The earliest and pathognomonic clinical manifestation of hypocalcemia is considered specific convulsions, tonic convulsions showed exceptional type.Fortunately, unlike clonic seizure, tetany is not a life-threatening condition of the patient, but her constant presence significantly impairs the quality of life of the patient.However, during prolonged tetany hypocalcemia develop serious consequences, which in some situations can provoke the development of death (laringotrahealny stridor, spasmodic contraction of the diaphragm and heart tetany with the subsequent development of asphyxia in patients in the postoperative period after surgical treatment of hypoparathyroidism).
to remote consequences of chronic hypocalcemia is cataract, generalized calcification, neuropsychiatric disorders, habitual miscarriage and fetal form of secondary infertility, chronic activation of foci of infection.
classical clinical course of tetany when gipokaltsiemicheskih syndrome is widespread signs of paresthesia, increased seizure and difficulty breathing act.The primary localization of sensory loss is the skin of the lips, and then spread on the skin distal extremities.In a situation where the tonic convulsions occurs locally, forming specific "karpopedalny syndrome" or "a sardonic mask."
specific symptoms of hypocalcemia is tetany in the presence of precursors in the form of dysarthria, dysphagia, paresis of cranial nerves, stem neurological disorders and spastic paresis of the limbs.Also, in most cases, convulsive seizures accompanied by severe disorders of vegetative origin (functional dyspepsia, profuse sweating, nonspecific pain in the abdomen, bronchospasm).
In some situations hypocalcemic convulsions can occur atypically as a tonic-clonic seizures by type of epilepsy with a short period of loss of consciousness and even the development of hallucinatory psychosis.
Rare manifestations of hypocalcemia, simulating the clinical picture of other diseases, is tetany stomach and heart, and laryngospasm.In this situation it is a good tool for specific tests for spazmofilii, skills that should have any specialist medical profile.
Hypocalcemia in children
Signs hypocalcemic syndrome may occur in a child in any age period, but the risk of this disease among newborns Children born prematurely as well as children born to a woman suffering from a severe form of diabetes.A typical manifestation of hypocalcemia in babies born prematurely, is a complete lack of severity depending on the level of hypocalcemia laboratory parameters, that is, in many situations, heavy "laboratory hypocalcemia" asymptomatic.
main etiopathogenetic factor that provokes the development of hypocalcemia in children of any age period is a nutritional, ie the lack of sufficient intake of baby vitamin D and calcium group.Supporting risk of provoking factors is the lack of protein in the blood of the child mainly albumin fraction and less failure of the parathyroid glands.
Clinical manifestations of hypocalcemia in children are similar to adult patients with the only difference being that the intensity of their symptoms more pronounced, and the risk of complications of this condition is high enough.The appearance of the child's symptoms in the form of laryngospasm can not perform a full breath, noisy breathing and loud cough needs immediate medical intervention and subsequent hospitalization to determine the level of calcium in the blood serum and further correction of hypocalcemia.For drugs
emergency in acute hypocalcemia in children include calcium gluconate solution at 10% in the calculated dose of 1 ml / 1 kg baby weight by intravenous injection in combination with 200 mg of elemental calcium.
Treatment of hypocalcemia
preferred direction in the treatment of hypocalcemic syndrome is a replacement therapy using drugs containing a high concentration of calcium, however, the key to successful correction of the pathological condition is to eliminate the root causes of hypocalcemia.Monitoring the effectiveness of substitution treatment is performed by carrying out laboratory evaluation of calcium in the blood serum and the target value in this situation is the indicator of 2.4 mmol / l, provided the index excretory calcium is less than 10 mmol / L.
most favorable to treat hypocalcemia one is the development of low calcium content in blood serum against unmodified of calcium absorption in the small intestine, as in this situation, the positive effect of ongoing replacement therapy occurs sufficiently rapidly and is persistent.This variant is assigned to a short course of therapy without additional administration of vitamin D. Group
In most cases, replacement therapy with calcium reinforced by the appointment of vitamin D, and the dose is adjusted individually, depending on the underlying cause of hypocalcemia.For example, in a situation where hypocalcemia was a complication of severe demineralization of bone, it is advisable to use vitamin D to the maximum saturation daily dose (Calcium D3 Nycomed 1 tablet 3 p. / D., Akvadetrim 2 drops per day orally), subject to mandatory control laboratoryCalcium indicators in order to prevent the development of hypercalcemic syndrome.Calcitriol therapy at a dose of 0.25 mg or alfacalcidol in a dose of 1 g does not need supplemental calcium and is supported by a correction of the patient's eating behavior (eating foods containing a high concentration of calcium, which is used as the active prevention of hypocalcemia).
In a situation where the patient holds the development of clinical symptom hypocalcemic attack of tetany, you must provide the patient a full range of emergency measures, the first step of which is the immediate introduction of a 10% solution of calcium chloride intravenously at a dose of 10 ml, paying special attention to the place of injection, sinceas the flow of the drug into the surrounding soft tissue is fraught with development of necrotic changes.The analog of the drug, is considered to be devoid of the side effects of calcium gluconate 10% solution at a dose of 40 ml.
lack of pronounced effect on the application of calcium chloride shows the development of the patient alkalosis or hypomagnesemia, which quickly eliminated by intravenous administration of 5% solution of ascorbic acid at a dose of 10 ml.After arresting attack tetanic seizures follow recommended intake of vitamin D group and calcium supplementation in the form of combined preparations orally.